US President Donald Trump on Friday tweeted an apparent warning to James Comey, the former FBI Director he recently fired.

"James Comey better hope that there are no 'tapes' of our conversations before he starts leaking to the press," Trump wrote.

In another tweet, Trump brought up the fact that James Clapper, the former Director of National Intelligence, has testified before the Senate that he was unaware of any evidence showing links between Trump's campaign and Russia.

Trump also tweeted that the allegations of Russian meddling in the 2016 US election was "fabricated by the Democrats as an excuse for losing the election."